Pfizer/BioNTech says its vaccine is 100% effective

Clinical trial results of Pfizer/BioNTech’s Covid-19 vaccine showed its efficacy is 100% and it is well tolerated in youths ages 12 to 15, the companies said Wednesday.Clinical trial results of Pfizer/BioNTech’s Covid-19 vaccine showed its efficacy is 100% and it is well tolerated in youths ages 12 to 15, the companies said Wednesday.